RESEARCH PLAN ? Summary/Abstract This project develops and applies methods to compare the overall personal well-being of different individuals using answers to survey questions asking respondents to rate many aspects of well-being. Comparing well-being across individuals and groups is a crucial input to many scientific endeavors: (1) using cross-sectional data to study the determinants of well-being or to study changes in well-being over the life course, (2) studying inequality in well-being, which in turn is necessary for aggregating personal well-being into a measure of social welfare, and (3) quantifying the extent of group advantage or disadvantage when nonmarket goods are taken into account. Two key issues arise in comparing overall personal well-being between individuals (or groups): first, different individuals may use the reporting scale differently; second, being able to compare any pair of individuals A and B requires being able to make an assessment of who has higher overall personal well-being when A has a higher level of some aspects of well- being, but B has a higher level of other aspects of well-being. Specific Aim 1 addresses scale-use differences: Develop and validate methods to compare the levels of self-reported aspects of well-being, such as emotions, pain, and perceived capabilities in daily life, across individuals and across groups in a way that adjusts for systematic differences in response styles and self-report biases. Specific Aim 2 addresses the question of how to deal with comparisons when one individual has higher levels of some aspects of well-being, while the other individual has higher levels of other aspects of well-being: Develop the theoretical foundation for a new interpersonally-comparable well-being measure, consistent with the equivalence approach in welfare theory, and adapted to use empirically with multidimensional subjective well-being measures (in conjunction with the scale-use-correction methods in Specific Aim 1). Specific Aim 3 involves data collection, empirical analysis, and theory to apply these methods to studying changes in well-being over time and over the life course: To better understand the patterns of, and reasons for, the movement of different aspects of well-being over the life course, collect two waves of highly multi-dimensional data on self- reported aspects of well-being along with questions for scale-use correction (see Specific Aim 1), on a survey that provides a rich trove of complementary data. Develop a theoretical framework for these measures in an economic model of life-cycle behavior that includes a wide variety of activities, investment decisions, and life circumstances. Apply the data in this framework to test new and existing theories about the determinants of well-being over the life course, why existing research finds a mid-life trough in the levels of many aspects of well-being, and how to distinguish permanent from transitory inequality in well-being.